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51.
Sajid ZI Anwar F Shabir G Rasul G Alkharfy KM Gilani AH 《Molecules (Basel, Switzerland)》2012,17(4):3917-3932
This study appraises the antioxidant and antimicrobial attributes of various solvent extracts (absolute methanol, aqueous methanol, absolute ethanol, aqueous ethanol, absolute acetone, aqueous acetone, and deionized water) from bark, leaves and seeds of Pongamia pinnata (L.) Pierre. Maximum extraction yield of antioxidant components from bark (16.31%), leaves (11.42%) and seeds (21.51%) of P. pinnata was obtained using aqueous methanol (20:80). Of the extracts tested, the bark extract, obtained with aqueous methanol, exhibited greater levels of total phenolics [6.94 g GAE/100 g dry weight (DW)], total flavonoids (3.44 g CE/100 g DW), inhibition of linoleic acid peroxidation (69.23%) and DPPH radical scavenging activity (IC(50) value, 3.21 μg/mL), followed by leaves and seeds extracts. Bark extract tested against a set of bacterial and fungal strains also revealed the strongest antimicrobial activity with the largest inhibition zone and lowest minimum inhibitory concentration (MIC). HPLC analysis of aqueous methanol extracts from bark, leaves and seeds indicated the presence of protocatechuic, ellagic, ferulic, gallic, gentisic, 4-hydroxybenzoic and 4-hydroxycinnamic acids in bark (1.50-6.70 mg/100 g DW); sorbic, ferulic, gallic, salicylic and p-coumaric acids in leaves (1.18-4.71 mg/100 g DW); vanillic, gallic and tannic acids in seeds (0.52-0.65 mg/100 g DW) as the main phenolic acids. The present investigation concludes that the tested parts of P. pinnata, in particular the bark, have strong potential for the isolation of antioxidant and antimicrobial agents for functional food and pharmaceutical uses. 相似文献
52.
E. U. Khan I. E. Qureshi J. J. Baluch M. I. Shahzad S. Karim M. Sajid F. Malik S. N. Husaini H. A. Khan 《Radiation measurements》2001,34(1-6):227-230
The interactions of 208Pb projectiles with natU target have been studied at 14.0 MeV/u beam energy using two different threshold detectors; mica and lexan. The elastic scattering data have been separated from the binary events and used for the determination of quarter-point angle θ1/4 (≡ grazing angle θgr). The values of maximum angular momentum
, radius of interaction Rint and reaction cross-section σRexp(el.) were then deduced by making use of the value of θ1/4. The data of inelastic events of different multiplicities have been used to determine partial reaction cross-sections. The sum of the partial cross-sections, therefore, yielded another independent value of reaction cross-section σRexp(inel.) that in turn was used to derive the alternative values of
, θgr, and Rint independently. The average of these quantities provided the experimental values of the reaction parameters that are comparable to the theoretical predictions. 相似文献
53.
McAlister proved that a necessary and sufficient condition for a regular semigroup S to be locally inverse is that it can be embedded as a quasi-ideal in a semigroup T which satisfies the following two conditions: (1) T = TeT, for some idempotent e; and (2) eTe is inverse. We generalise this result to the class of semigroups with local units in which all local submonoids have commuting idempotents. 相似文献
54.
Mujahid Farid Muhammad Abubakar Zaki Ul Zaman Asam Wajiha Sarfraz Mohsin Abbas Muhammad Bilal Shakoor Shafaqat Ali Sajid Rashid Ahmad Asim Jilani Javed Iqbal Abdullah G. Al-Sehemi Omar A. Al-Hartomy 《Molecules (Basel, Switzerland)》2022,27(13)
We investigated how different doses of microwave irradiation (MR) affect seed germination in Sorghum, including the level of remediation against textile and surgical wastewater (WW) by modulating biochemical and morpho-physiological mechanisms under glutamic acid (GA) application. The experiment was conducted to determine the impact of foliar-applied GA on Sorghum under wastewater conditions. Plants were treated with or without microwave irradiation (30 s, 2.45 GHz), GA (5 and 10 mM), and wastewater (0, 25, 50, and 100). Growth and photosynthetic pigments were significantly decreased in plants only treated with various concentrations of WW. GA significantly improved the plant growth characteristics both in MR-treated and -untreated plants compared with respective controls. HMs stress increased electrolyte leakage (EL), hydrogen peroxide (H2O2), and malondialdehyde (MDA) content; however, the GA chelation significantly improved the antioxidant enzymes activities such as ascorbate oxidase (APX), superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) both in MR-treated and -untreated plants under WW stress compared with respective controls. The results suggested that the MR-treated plants accumulate higher levels of HMs under GA addition in comparison to the WW-only-treated and MR-untreated plants. The maximum increase in Cd accumulation was observed in the range of 14–629% in the roots, 15–2964% in the stems, and 26–4020% in the leaves; the accumulation of Cu was 18–2757% in the roots, 15–4506% in the stems, and 23–4605% in the leaves; and the accumulation of Pb was 13–4122% in the roots, 21–3588% in the stems, and 21–4990% in the leaves under 10 mM GA and MR-treated plants. These findings confirmed that MR-treated sorghum plants had a higher capacity for HMs uptake under GA and could be used as a potential candidate for wastewater treatment. 相似文献
55.
Moniba Sajid Muhammad Rashid Khan Muhammad Umar Ijaz Hammad Ismail Muhammad Zeeshan Bhatti Sayed Afzal Shah Saima Ali Muhammad Usman Tareen Saqer S. Alotaibi Sarah M. Albogami Gaber El-Saber Batiha 《Molecules (Basel, Switzerland)》2022,27(14)
In the current study, the anti-inflammatory and analgesic potential of Alnus nitida (leaves and fruits) was evaluated in the Sprague-Dawley rat. Traditionally, A. nitida was used for the treatment of inflammatory ailments. However, A. nitida leaves and fruits have not been yet reported regarding any potential medicinal effects. Leaves/fruits of A. nitida were extracted with methanol and fractionated to attain n-hexane, chloroform, ethyl acetate and aqueous fractions. These extracts were then evaluated for in vivo analgesic and anti-inflammatory potential. For in vivo anti-inflammatory activity, carrageenan-induced paw edema assay, Freunds’ complete adjuvant-induced edema, xylene-induced ear edema and histamine-induced paw edema models were used in rats, which showed significant (p < 0.01) reduction (70–80%) in edema in comparison of inflammatory controls. On other hand, for the analgesic assessment, hot plate assay and acetic acid-induced writhing tests were used, which showed a significant (p < 0.01) rise in latency time (40–60%) as compared with pain-induced controls. These results were comparable with standard drugs in a concentration-dependent manner and no mortality or toxicity was observed during all experiments. Then, for the identification of chemical constituents gas chromatography–mass spectrometry (GC-MS) analysis was performed, which indicated the presence of neophytadiene, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol, phytol and vitamin E, justifying the use of A. nitida to treat inflammatory disorders. 相似文献
56.
Shahida Sadiqi Muhammad Hamza Farooq Ali Sadia Alam Qismat Shakeela Shehzad Ahmed Asma Ayaz Sajid Ali Saddam Saqib Fazal Ullah Wajid Zaman 《Molecules (Basel, Switzerland)》2022,27(19)
Some soil microbes, with their diverse inhabitance, biologically active metabolites, and endospore formation, gave them characteristic predominance and recognition among other microbial communities. The present study collected ten soil samples from green land, agricultural and marshy soil sites of Khyber Pakhtunkhwa, Pakistan. After culturing on described media, the bacterial isolates were identified through phenotypic, biochemical and phylogenetic analysis. Our phylogenetic analysis revealed three bacterial isolates, A6S7, A1S6, and A1S10, showing 99% nucleotides sequence similarity with Brevibacillus formosus, Bacillus Subtilis and Paenibacillus dendritiformis. The crude extract was prepared from bacterial isolates to assess the anti-bacterial potential against various targeted multidrug-resistant strains (MDRS), including Acinetobacter baumannii (ATCC 19606), Methicillin-resistant Staphylococcus aureus (MRSA) (BAA-1683), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (BAA-2108), Staphylococcus aureus (ATCC 292013), Escherichia coli (ATCC25922) and Salmonella typhi (ATCC 14028). Our analysis revealed that all bacterial extracts possess activity against Gram-negative and Gram-positive bacteria at a concentration of 5 mg/mL, efficiently restricting the growth of E. coli compared with positive control ciprofloxacin. The study concluded that the identified species have the potential to produce antimicrobial compounds which can be used to control different microbial infections, especially MDRS. Moreover, the analysis of the bacterial extracts through GC-MS indicated the presence of different antimicrobial compounds such as propanoic acid, oxalic acid, phenol and hexadecanoic acid. 相似文献
57.
Umar Farooq Sara Khan Sadia Naz Tanveer A. Wani Syed Majid Bukhari Abullahi Tunde Aborode Sohail Anjum Shahzad Seema Zargar 《Molecules (Basel, Switzerland)》2022,27(15)
(1) Background: Achillea mellifolium belongs to a highly reputed family of medicinal plants, with plant extract being used as medicine in indigenous system. However, limited data is available regarding the exploitation of the medicinal potential of isolated pure compounds from this family; (2) Methods: A whole plant extract was partitioned into fractions and on the basis of biological activity, an ethyl acetate fraction was selected for isolation of pure compounds. Isolated compounds were characterized using different spectroscopic techniques. The compounds isolated from this study were tested for their medicinal potential using in-vitro enzyme assay, coupled with in-silico studies; (3) Results: Three new acrylic acid derivatives (1–3) have been isolated from the ethyl acetate fraction of Achillea mellifolium. The characterization of these compounds (1–3) was carried out using UV/Vis, FT-IR, 1D and 2D-NMR spectroscopy (1H-NMR, 13C-NMR, HMBC, NOESY) and mass spectrometry. These acrylic acid derivatives were further evaluated for their enzyme inhibition potential against urease from jack bean and α glucosidase from Saccharomyces cerevisiae, using both in-silico and in-vitro approaches. In-vitro studies showed that compound 3 has the highest inhibition against urease enzyme (IC50 =10.46 ± 0.03 μΜ), followed by compound 1 and compound 2 with percent inhibition and IC50 value of 16.87 ± 0.02 c and 13.71 ± 0.07 μΜ, respectively, compared to the standard (thiourea-IC50 = 21.5 ± 0.01 μΜ). The investigated IC50 value of compound 3 against the urease enzyme is two times lower compared to thiourea, suggesting that this compound is twice as active compared to the standard drug. On the other hand, all three compounds (1–3) revealed mild inhibition potential against α-glucosidase. In-silico molecular docking studies, in combination with MD simulations and free energy, calculations were also performed to rationalize their time evolved mode of interaction inside the active pocket. Binding energies were computed using a MMPBSA approach, and the role of individual residues to overall binding of the inhibitors inside the active pockets were also computed; (4) Conclusions: Together, these studies confirm the inhibitory potential of isolated acrylic acid derivatives against both urease and α-glucosidase enzymes; however, their inhibition potential is better for urease enzyme even when compared to the standard. 相似文献
58.
Dr. Liliyana Zaayter Dr. Mattia Mori Tanveer Ahmad Dr. Waseem Ashraf Dr. Christian Boudier Dr. Vasyl Kilin Dr. Krishna Gavvala Dr. Ludovic Richert Dr. Sylvia Eiler Dr. Marc Ruff Dr. Maurizio Botta Dr. Christian Bronner Dr. Marc Mousli Prof. Yves Mély 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13363-13375
During DNA replication, ubiquitin-like, containing PHD and RING fingers domains 1 (UHRF1) plays key roles in the inheritance of methylation patterns to daughter strands by recognizing through its SET and RING-associated domain (SRA) the methylated CpGs and recruiting DNA methyltransferase 1 (DNMT1). Herein, our goal is to identify UHRF1 inhibitors targeting the 5′-methylcytosine (5mC) binding pocket of the SRA domain to prevent the recognition and flipping of 5mC and determine the molecular and cellular consequences of this inhibition. For this, we used a multidisciplinary strategy combining virtual screening and molecular modeling with biophysical assays in solution and cells. We identified an anthraquinone compound able to bind to the 5mC binding pocket and inhibit the base-flipping process in the low micromolar range. We also showed in cells that this hit impaired the UHRF1/DNMT1 interaction and decreased the overall methylation of DNA, highlighting the critical role of base flipping for DNMT1 recruitment and providing the first proof of concept of the druggability of the 5mC binding pocket. The selected anthraquinone appears thus as a key tool to investigate the role of UHRF1 in the inheritance of methylation patterns, as well as a starting point for hit-to-lead optimizations. 相似文献
59.
This experimental study of quasi-two-dimensional grid turbulence in gravity-driven soap-film flow focuses on the differences
between the behavior of the flow and the theoretical picture of two-dimensional turbulence. A previously unattainable quality
of velocity field acquisition facilitates simultaneous measurement of velocity field features in the scale range spanning
over two orders of magnitude. The highly-resolved flow field data are analyzed statistically in terms of velocity structure
functions, as well as energy and enstrophy averages at different downstream positions. We find the rate of decay of these
averages to be quantifiably greater than the predictions of the two-dimensional turbulence theory. This increased decay is
likely to be the manifestation of the extra dissipation mechanism present in soap-film flows and prominent on the larger scales—air
drag. The structure function analysis confirms the notion.
This research was supported by Los Alamos National Laboratory, task order BG109. 相似文献
60.
Analysis of Solvent Effect on Mechanical Properties of Poly(ether ether ketone) Using Nano-indentation 下载免费PDF全文
Tanveer Iqbal Saima Yasin Ahmad Shakeel Hamayoun Mahmood Fahad Nazir Paul F. Luckham 《化学物理学报(中文版)》2018,31(2):211-215
Poly (ether ether ketone)(PEEK) is a high-performance semi-crystalline thermoplastic polymer.Exposure of the polymeric surface to solvents can have a strong effect like softening/swelling of polymeric network or dissolution.In this study, nano-indentation analysis was performed to study the effect of acetone on the surface mechanical properties of PEEK using different exposure time.The experiments were performed with a constant loading rate (10 nm/s) to a maximum indentation displacement (1000 nm).A 30-second hold segment was included at the maximum load to account for any creep effects followed by an unloading segment to 80% unloading.The indentation hardness and the elastic modulus were computed as a continuous function of the penetration displacement in the continuous stiffness mode (CSM) indentation.The experimental data showed that the peak load decreased from ~5.2 mN to ~1.7 mN as exposure time in solvent environment increased from 0 to 18 days.The elastic modulus and the hardness of PEEK samples also displayed a decreasing trend as a function of exposure time in the solvent environment.Two empirical models were used to fit the experimental data of hardness as a function of exposure time which showed a good agreement with the experimental values. 相似文献